This article was prepared by Professor Kane for a public lecture while he was the Professorial Fellow of Monetary and Financial Economics at Victoria University in 2005. Prudential regulation seeks to assure the safety and soundness of the financial sector. The article considers the regulation of banks operating in both Australia and New Zealand. It discusses differences in the regulatory cultures of the two countries, and identifies preconditions for arriving at a fair and harmonised system of regulation. A harmonised regulatory regime is one that maximises the welfare of the citizens across countries, rather than simply blending together two national regulatory regimes. The article stresses the importance of proper processes for the resolution of incentive conflicts between countries that may arise in regulation and crisis situations.